Walmart sells night crawlers which I'm pretty sure are chemical free. Earthworms and other invertebrates of that nature are the only things i recommend giving to your frog live. I certainly think that feeding an ADF to your ACF is uncalled for and inhumane. Also, ADFs are much more likely to have parasites
which may harm or potentially kill your frog. ACFs and other aquatic frogs should never really be handled ever. Use a net or some other container to scoop them up when feeding.